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Detecting Broken Pointcuts Using Structural Commonality And Degree Of Interest, Raffi Khatchadourian, Awais Rashd, Hidehiko Masuhara, Takuya Watanabe Nov 2015

Detecting Broken Pointcuts Using Structural Commonality And Degree Of Interest, Raffi Khatchadourian, Awais Rashd, Hidehiko Masuhara, Takuya Watanabe

Publications and Research

Pointcut fragility is a well-documented problem in Aspect-Oriented Programming; changes to the base code can lead to join points incorrectly falling in or out of the scope of pointcuts. Deciding which pointcuts have broken due to base-code changes is daunting, especially in large and complex systems. We present an automated approach that recommends pointcuts that are likely to require modification due to a certain base-code change and ones that do not. Our hypothesis is that join points selected by a pointcut exhibit common structural characteristics. Patterns describing such commonalities recommend pointcuts that have potentially broken to the developer. The approach …

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'At-Risk' Places: Inequaties In The Distribution Of Environmental Stressors And Prescription Rates Of Mental Health Medications In Glasgow, Scotland, Juliana A. Maantay, Andrew Maroko Oct 2015

'At-Risk' Places: Inequaties In The Distribution Of Environmental Stressors And Prescription Rates Of Mental Health Medications In Glasgow, Scotland, Juliana A. Maantay, Andrew Maroko

Publications and Research

Using geospatial analytical methods, this study examines the association between one aspect of the built environment, namely, the concentration of vacant and derelict land (VDL), and the prevalence of mental health disorders (using the proxy variable of mental health medication prescription rates) in Glasgow, Scotland. This study builds on our previous research, which demonstrated the spatial correspondence between the locations of VDL in Glasgow and several physical health outcomes. Numerous studies of other locales have found similar correspondence between different elements of the built environment and various health outcomes. This is the first study of its kind to look at …

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Rag-3d: A Search Tool For Rna 3d Substructures, Mai Zahran, Cigdem Sevim Bayrak, Shereef Elmetwaly, Tamar Schlick Oct 2015

Rag-3d: A Search Tool For Rna 3d Substructures, Mai Zahran, Cigdem Sevim Bayrak, Shereef Elmetwaly, Tamar Schlick

Publications and Research

To address many challenges in RNA structure/function prediction, the characterization of RNA's modular architectural units is required. Using the RNA-As-Graphs (RAG) database, we have previously explored the existence of secondary structure (2D) submotifs within larger RNA structures. Here we present RAG-3D—a dataset of RNA tertiary (3D) structures and substructures plus a web-based search tool—designed to exploit graph representations of RNAs for the goal of searching for similar 3D structural fragments. The objects in RAG-3D consist of 3D structures translated into 3D graphs, cataloged based on the connectivity between their secondary structure elements. Each graph is additionally described in terms of …

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Reinforcing Endothelial Junctions Prevents Microvessel Permeability Increase And Tumor Cell Adhesion In Microvessels In Vivo, Bingmei M. Fu, Jinlin Yang, Bin Cai, Jie Fan, Lin Zhang, Min Zeng Oct 2015

Reinforcing Endothelial Junctions Prevents Microvessel Permeability Increase And Tumor Cell Adhesion In Microvessels In Vivo, Bingmei M. Fu, Jinlin Yang, Bin Cai, Jie Fan, Lin Zhang, Min Zeng

Publications and Research

Tumor cell adhesion to the microvessel wall is a critical step during tumor metastasis. Vascular endothelial growth factor (VEGF), a secretion of tumor cells, can increase microvessel permeability and tumor cell adhesion in the microvessel. To test the hypothesis that inhibiting permeability increase can reduce tumor cell adhesion, we used in vivo fluorescence microscopy to measure both microvessel permeability and adhesion rates of human mammary carcinoma MDA-MB-231 cells in post-capillary venules of rat mesentery under the treatment of VEGF and a cAMP analog, 8-bromo-cAMP, which can decrease microvessel permeability. By immunostaining adherens junction proteins between endothelial cells forming the microvessel …

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Supporting Teachers’ Learning About Mathematical Modeling, June L. Gastón, Barbara A. Lawrence Oct 2015

Supporting Teachers’ Learning About Mathematical Modeling, June L. Gastón, Barbara A. Lawrence

Publications and Research

In the United States, one of the Standards for Mathematical Practice of the Common Core Curriculum (Common Core State Standards Initiative, 2010) is Model with mathematics. This standard requires that students be taught in a manner that will enable them to ―apply the mathematics they know to solve problems arising in everyday life, society, and the workplace‖ (p. 7). However many prospective and practicing teachers acquire a pedagogical style that does not support this standard. To promote higher levels of student thinking associated with mathematical modeling, teachers must thus be taught not only what mathematical modeling is, but how it …

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Hohenberg-Kohn Theorems In Electrostatic And Uniform Magnetostatic Fields, Xiao-Yin Pan, Viraht Sahni Oct 2015

Hohenberg-Kohn Theorems In Electrostatic And Uniform Magnetostatic Fields, Xiao-Yin Pan, Viraht Sahni

Publications and Research

The Hohenberg-Kohn (HK) theorems of bijectivity between the external scalar potential and the gauge invariant nondegenerate ground state density, and the consequent Euler variational principle for the density, are proved for arbitrary electrostatic field and the constraint of fixed electron number. The HK theorems are generalized for spinless electrons to the added presence of an external uniform magnetostatic field by introducing the new constraint of fixed canonical orbital angular momentum. Thereby a bijective relationship between the external scalar and vector potentials, and the gauge invariant nondegenerate ground state density and physical current density, is proved. A corresponding Euler variational principle …

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Probing Molecular Dynamics At The Nanoscale Via An Individual Paramagnetic Centre, T. Staudacher, N. Raatz, S. Pezzagna, J. Meijer, F. Reinhard, C. A. Meriles, J. Wrachtrup Oct 2015

Probing Molecular Dynamics At The Nanoscale Via An Individual Paramagnetic Centre, T. Staudacher, N. Raatz, S. Pezzagna, J. Meijer, F. Reinhard, C. A. Meriles, J. Wrachtrup

Publications and Research

We demonstrate a protocol using individual nitrogen-vacancy centres in diamond to observe the time evolution of proton spins from organic molecules located a few nanometres from the diamond surface. The protocol records temporal correlations among the interacting protons, and thus is sensitive to the local dynamics via its impact on the nuclear spin relaxation and interaction with the nitrogen vacancy. We gather information on the nanoscale rotational and translational diffusion dynamics by analysing the time dependence of the nuclear magnetic resonance signal. Applying this technique to liquid and solid samples, we find evidence that liquid samples form a semi-solid layer …

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Cladribine Analogues Via O6-(Benzotriazolyl) Derivatives Of Guanine Nucleosides, Sakilam Satishkumar, Prasanna K. Vuram, Siva Subrahmanyam Relangi, Venkateshwarlu Gurram, Hong Zhou, Robert J. Kreitman, Michelle M. Martínez Montemayor, Lijia Yang, Muralidharan Kaliyaperumal, Somesh Sharma, Narender Pottabathini, Mahesh K. Lakshman Oct 2015

Cladribine Analogues Via O6-(Benzotriazolyl) Derivatives Of Guanine Nucleosides, Sakilam Satishkumar, Prasanna K. Vuram, Siva Subrahmanyam Relangi, Venkateshwarlu Gurram, Hong Zhou, Robert J. Kreitman, Michelle M. Martínez Montemayor, Lijia Yang, Muralidharan Kaliyaperumal, Somesh Sharma, Narender Pottabathini, Mahesh K. Lakshman

Publications and Research

Cladribine, 2-chloro-2′-deoxyadenosine, is a highly efficacious, clinically used nucleoside for the treatment of hairy cell leukemia. It is also being evaluated against other lymphoid malignancies and has been a molecule of interest for well over half a century. In continuation of our interest in the amide bond-activation in purine nucleosides via the use of (benzotriazol-1yl-oxy)tris(dimethylamino)phosphonium hexafluorophosphate, we have evaluated the use of O6-(benzotriazol-1-yl)-2′-deoxyguanosine as a potential precursor to cladribine and its analogues. These compounds, after appropriate deprotection, were assessed for their biological activities, and the data are presented herein. Against hairy cell leukemia (HCL), T-cell lymphoma (TCL) and chronic lymphocytic …

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Two Distinct Modes Of Metal Ion Binding In The Nuclease Active Site Of A Viral Dna-Packaging Terminase: Insight Into The Two-Metal-Ion Catalytic Mechanism, Haiyan Zhao, Zihan Lin, Anna Y. Lynn, Brittany Varnado, John A. Beutler, Ryan P. Murelli, Stuart F.J. Le Grice, Liang Tang Oct 2015

Two Distinct Modes Of Metal Ion Binding In The Nuclease Active Site Of A Viral Dna-Packaging Terminase: Insight Into The Two-Metal-Ion Catalytic Mechanism, Haiyan Zhao, Zihan Lin, Anna Y. Lynn, Brittany Varnado, John A. Beutler, Ryan P. Murelli, Stuart F.J. Le Grice, Liang Tang

Publications and Research

Many dsDNA viruses encode DNA-packaging terminases, each containing a nuclease domain that resolves concatemeric DNA into genome-length units. Terminase nucleases resemble the RNase H-superfamily nucleotidyltransferases in folds, and share a two-metal-ion catalytic mechanism. Here we show that residue K428 of a bacteriophage terminase gp2 nuclease domain mediates binding of the metal cofactor Mg2+. A K428A mutation allows visualization, at high resolution, of a metal ion binding mode with a coupled-octahedral configuration at the active site, exhibiting an unusually short metal-metal distance of 2.42 A° . Such proximity of the two metal ions may play an essential role in catalysis by …

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Interdisciplinary Teams In The First Year Experience, Nicola Blake Oct 2015

Interdisciplinary Teams In The First Year Experience, Nicola Blake

Publications and Research

No abstract provided.

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Opening Up The Dialogue Across Disciplines: Making Room For Inquiry And Creativity From Pre-Kindergarten Through University, Amanda Nicole Gulla, Limor Pinhasi-Vittorio, Alison Lehner-Quam Oct 2015

Opening Up The Dialogue Across Disciplines: Making Room For Inquiry And Creativity From Pre-Kindergarten Through University, Amanda Nicole Gulla, Limor Pinhasi-Vittorio, Alison Lehner-Quam

Publications and Research

Professional development with teachers, whether they are in pre-K-12 schools or in higher education, creates opportunities for discussions among teachers and teacher educators about how to find spaces for creativity and the imagination within the struc- ture of the Common Core State Standards, a set of national standards adopted on a state- by-state basis in the U.S. Two education faculty members and an education librarian from a large city university held workshops, bringing together university faculty in arts and humanities, science, mathematics and education, and pre-K-12 teachers to explore the potential for inquiry and creativity in the Common Core State …

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Deleuze, Haraway, And The Radical Democracy Of Desire, Robert Leston Oct 2015

Deleuze, Haraway, And The Radical Democracy Of Desire, Robert Leston

Publications and Research

In response to suggestions that Deleuze and Guattari are the “enemy” of companion species, this essay explores the tension between Donna Haraway’s attacks against Deleuze and Guattari and their philosophy of becoming animal. The essay goes on to contextualize Deleuze and Guattari’s statements against pet owners through a discussion of the psychoanalytical refiguration of desire and shows how their ostensible attack against pet owners fits into their larger critique against capitalism. The essay illustrates why Deleuze and Guattari and Haraway are more in agreement than first meets the eye, finding commensurability through Haraway’s early work on embryology. Becoming animal does …

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Porting The Netbeans Java 8 Enhanced For Loop Lambda Expression Refactoring To Eclipse, Md Arefin, Raffi Khatchadourian Oct 2015

Porting The Netbeans Java 8 Enhanced For Loop Lambda Expression Refactoring To Eclipse, Md Arefin, Raffi Khatchadourian

Publications and Research

Java 8 is one of the largest upgrades to the popular language and framework in over a decade. However, the Eclipse IDE is missing several key refactorings that could help developers take advantage of new features in Java 8 more easily. In this paper, we discuss our ongoing work in porting the enhanced for loop to lambda expression refactoring from the NetBeans IDE to Eclipse. We also discuss future plans for new Java 8 refactorings not found in any current IDE.

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Porting The Netbeans Java 8 Enhanced For Loop Lambda Expression Refactoring To Eclipse, Md Arefin, Raffi Khatchadourian Oct 2015

Porting The Netbeans Java 8 Enhanced For Loop Lambda Expression Refactoring To Eclipse, Md Arefin, Raffi Khatchadourian

Publications and Research

Java 8 is one of the largest upgrades to the popular language and framework in over a decade. However, the Eclipse IDE is missing several key refactorings that could help developers take advantage of new features in Java 8 more easily. In this paper, we discuss our ongoing work in porting the enhanced for loop to lambda expression refactoring from the NetBeans IDE to Eclipse. We also discuss future plans for new Java 8 refactorings not found in any current IDE.

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Fraglight: Shedding Light On Broken Pointcuts In Evolving Aspect-Oriented Software, Raffi Khatchadourian, Awais Rashid, Hidehiko Masuhara, Takuya Watanabe Oct 2015

Fraglight: Shedding Light On Broken Pointcuts In Evolving Aspect-Oriented Software, Raffi Khatchadourian, Awais Rashid, Hidehiko Masuhara, Takuya Watanabe

Publications and Research

Pointcut fragility is a well-documented problem in Aspect-Oriented Programming; changes to the base code can lead to join points incorrectly falling in or out of the scope of pointcuts. Deciding which pointcuts have broken due to base-code changes is daunting, especially in large and complex systems. We demonstrate an automated tool called FRAGLIGHT that recommends a set of pointcuts that are likely to require modification due to a certain base-code change. The underlying approach is rooted in harnessing unique and arbitrarily deep structural commonality between program elements corresponding to join points selected by a pointcut in a particular software version. …

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An Evolutionary Vaccination Game In The Modified Activity Driven Network By Considering The Closeness, Dun Han, Mei Sun Sep 2015

An Evolutionary Vaccination Game In The Modified Activity Driven Network By Considering The Closeness, Dun Han, Mei Sun

Publications and Research

In this paper, we explore an evolutionary vaccination game in the modified activity driven network by considering the closeness. We set a closeness parameter p which is used to describe the way of connection between two individuals. The simulation results show that the closeness p may have an active role in weakening both the spreading of epidemic and the vaccination. Besides, when vaccination is not allowed, the final recovered density increases with the value of the ratio of the infection rate to the recovery rate λ/μ. However, when vaccination is allowed the final density of recovered individual first increases and …

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A Comparison Of Two Gluteus Maximus Emg Maximum Voluntary Isometric Contraction Positions, Bret Contreras, Andrew D. Vigotsky, Brad J. Schoenfeld, Chris Beardsley, John Cronin Sep 2015

A Comparison Of Two Gluteus Maximus Emg Maximum Voluntary Isometric Contraction Positions, Bret Contreras, Andrew D. Vigotsky, Brad J. Schoenfeld, Chris Beardsley, John Cronin

Publications and Research

Background. The purpose of this study was to compare the peak electromyography (EMG) of the most commonly-used position in the literature, the prone bent-leg (90°) hip extension against manual resistance applied to the distal thigh (PRONE), to a novel position, the standing glute squeeze (SQUEEZE). Methods. Surface EMG electrodes were placed on the upper and lower gluteus maximus of thirteen recreationally active females (age = 28.9 years; height = 164 cm; body mass = 58.2 kg), before three maximum voluntary isometric contraction (MVIC) trials for each position were obtained in a randomized, counterbalanced fashion. Results. No statistically significant (p < 0.05) differences were observed between PRONE (upper: 91.94%; lower: 94.52%) and SQUEEZE (upper: 92.04%; lower: 85.12%) for both the upper and lower gluteus maximus. Neither the PRONE nor SQUEEZE was more effective between all subjects. Conclusions. In agreement with other studies, no single testing position is ideal for every participant. Therefore, it is recommended that investigators employ multiple MVIC positions, when possible, to ensure accuracy. Future research should investigate a variety of gluteus maximus MVIC positions in heterogeneous samples.

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Molecular Helices As Electron Acceptors In High-Performance Bulk Heterojunction Solar Cells, Yu Zhong, M. Tuan Trinh, Rongsheng Chen, Geoffrey E. Purdum, Petr P. Khlyabich, Melda Sezen, Seokjoon Oh, Haiming Zhu, Brandon Fowler, Boyuan Zhang, Wei Wang, Chang-Yong Nam, Matthew Y. Sfeir, Charles T. Black, Michael L. Steigerwald, Yueh-Lin Loo, Fay Ng, X.-Y. Zhu, Colin Nuckolls Sep 2015

Molecular Helices As Electron Acceptors In High-Performance Bulk Heterojunction Solar Cells, Yu Zhong, M. Tuan Trinh, Rongsheng Chen, Geoffrey E. Purdum, Petr P. Khlyabich, Melda Sezen, Seokjoon Oh, Haiming Zhu, Brandon Fowler, Boyuan Zhang, Wei Wang, Chang-Yong Nam, Matthew Y. Sfeir, Charles T. Black, Michael L. Steigerwald, Yueh-Lin Loo, Fay Ng, X.-Y. Zhu, Colin Nuckolls

Publications and Research

Despite numerous organic semiconducting materials synthesized for organic photovoltaics in the past decade, fullerenes are widely used as electron acceptors in highly efficient bulk-heterojunction solar cells. None of the non-fullerene bulk heterojunction solar cells have achieved efficiencies as high as fullerene-based solar cells. Design principles for fullerene-free acceptors remain unclear in the field. Here we report examples of helical molecular semiconductors as electron acceptors that are on par with fullerene derivatives in efficient solar cells. We achieved an 8.3% power conversion efficiency in a solar cell, which is a record high for non-fullerene bulk heterojunctions. Femtosecond transient absorption spectroscopy revealed …

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2d (0,2) Quiver Gauge Theories And D-Branes, Sebastian Franco, Dongwook Ghim, Sangmin Lee, Rak-Kyeong Seong, Daisuke Yokoyama Sep 2015

2d (0,2) Quiver Gauge Theories And D-Branes, Sebastian Franco, Dongwook Ghim, Sangmin Lee, Rak-Kyeong Seong, Daisuke Yokoyama

Publications and Research

We initiate a systematic study of 2d(0,2) quiver gauge theories on the world-volume of D1-branes probing singular toric Calabi-Yau 4-folds. We present an algorithm for efficiently calculating the classical mesonic moduli spaces of these theories, which cor-respond to the probed geometries. We also introduce a systematic procedure for constructing the gauge theories for arbitrary toric singularities by means of partial resolution, which translates to higgsing in the field theory. Finally, we introduce Brane Brick Models, a novel class of brane configurations that consist of D4-branes suspended from an NS5-brane wrap-ping a holomorphic surface, tessellating a 3-torus. Brane Brick Models are …

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Pili-Induced Clustering Of N. Gonorrhoeae Bacteria, Johannes Taktikos, Yen Ting Lin, Holger Stark, Nicolas Biais, Vasily Zaburdaev Sep 2015

Pili-Induced Clustering Of N. Gonorrhoeae Bacteria, Johannes Taktikos, Yen Ting Lin, Holger Stark, Nicolas Biais, Vasily Zaburdaev

Publications and Research

Type IV pili (Tfp) are prokaryotic retractable appendages known to mediate surface attachment, motility, and subsequent clustering of cells. Tfp are the main means of motility for Neisseria gonorrhoeae, the causative agent of gonorrhea. Tfp are also involved in formation of the microcolonies, which play a crucial role in the progression of the disease. While motility of individual cells is relatively well understood, little is known about the dynamics of N. gonorrhoeae aggregation. We investigate how individual N. gonorrhoeae cells, initially uniformly dispersed on flat plastic or glass surfaces, agglomerate into spherical microcolonies within hours. We quantify the clustering process …

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Bulk Equations Of Motion From Cft Correlators, Daniel N. Kabat, Gilad Lifschytz Sep 2015

Bulk Equations Of Motion From Cft Correlators, Daniel N. Kabat, Gilad Lifschytz

Publications and Research

ToO (1/N) we derive, purely from CFT data, the bulk equations of motion for interacting scalar fields and for scalars coupled to gauge fields and gravity. We first uplift CFT operators to mimic local AdS fields by imposing bulk microcausality. This requires adding an infinite tower of smeared higher-dimension double-trace operators to the CFT definition of a bulk field, with coefficients that we explicitly compute. By summing the contribution of the higher-dimension operators we derive the equations of motion satisfied by these uplifted CFT operators and show that we precisely recover the expected bulk equations of motion. We exhibit the …

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A Mechanism For Biologically Induced Iodine Emissions From Sea Ice, A. Saiz-Lopez, Christopher S. Blaszczak-Boxe, L. J. Carpenter Sep 2015

A Mechanism For Biologically Induced Iodine Emissions From Sea Ice, A. Saiz-Lopez, Christopher S. Blaszczak-Boxe, L. J. Carpenter

Publications and Research

Ground- and satellite-based measurements have reported high concentrations of iodine monoxide (IO) in coastal Antarctica. The sources of such a large iodine burden in the coastal Antarctic atmosphere remain unknown.We propose a mechanism for iodine release from sea ice based on the premise that micro-algae are the primary source of iodine emissions in this environment. The emissions are triggered by the biological production of iodide (I�) and hypoiodous acid (HOI) from micro-algae (contained within and underneath sea ice) and their diffusion through sea-ice brine channels, ultimately accumulating in a thin brine layer (BL) on the surface of sea ice. Prior …

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Can Improved Agricultural Water Use Efficiency Save India’S Groundwater?, Ram Fishman, Naresh Devineni, Swaminathan Raman Aug 2015

Can Improved Agricultural Water Use Efficiency Save India’S Groundwater?, Ram Fishman, Naresh Devineni, Swaminathan Raman

Publications and Research

Irrigated agriculture is placing increasing pressure on finite freshwater resources, especially in developing countries, where water extraction is often unregulated, un-priced and even subsidized. To shift agriculture to a more sustainable use of water without harming the food security and livelihoods of hundreds of millions of smallholders, substantial improvements of water use efficiency will be required. Here, we use detailed hydroclimatic and agricultural data to estimate the potential for the widespread adoption of efficient irrigation technologies to halt the depletion of India's groundwater resources. Even though we find substantial technical potential for reversing water table declines, we show that the …

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Outcome Prediction In Mathematical Models Of Immune Response To Infection, Manuel Mai, Kun Wang, Greg Huber, Michael Kirby, Mark D. Shattuck, Corey S. O’Hern Aug 2015

Outcome Prediction In Mathematical Models Of Immune Response To Infection, Manuel Mai, Kun Wang, Greg Huber, Michael Kirby, Mark D. Shattuck, Corey S. O’Hern

Publications and Research

Clinicians need to predict patient outcomes with high accuracy as early as possible after disease inception. In this manuscript, we show that patient-to-patient variability sets a fundamental limit on outcome prediction accuracy for a general class of mathematical models for the immune response to infection. However, accuracy can be increased at the expense of delayed prognosis. We investigate several systems of ordinary differential equations (ODEs) that model the host immune response to a pathogen load. Advantages of systems of ODEs for investigating the immune response to infection include the ability to collect data on large numbers of ‘virtual patients’, each …

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Simulating And Animating The Spatial Dynamics Of Interacting Species Living On A Torus, Boyan Kostadinov Aug 2015

Simulating And Animating The Spatial Dynamics Of Interacting Species Living On A Torus, Boyan Kostadinov

Publications and Research

The goal of this talk is to present a student research project in computational population biology, which aims at creating a computer simulation and animation of the spatial dynamics of interactions between two kinds of species living on a torus-shaped universe. The habitat for spatial interactions is modeled by a 2D lattice with periodic boundary conditions, which wrap the rectangular grid into a torus. The spatial interactions between the species have two components: 1. Population dynamics modeled by the classical Nicholson-Bailey two-parameter family of models for coupled interactions between species, extended to incorporate space and 2. Two-parameter migration dynamics, modeled …

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Keeping A Good Attitude: A Quaternion-Based Orientation Filter For Imus And Margs, Roberto G. Valenti, Ivan Dryanovski, Jizhong Xiao Aug 2015

Keeping A Good Attitude: A Quaternion-Based Orientation Filter For Imus And Margs, Roberto G. Valenti, Ivan Dryanovski, Jizhong Xiao

Publications and Research

Orientation estimation using low cost sensors is an important task for Micro Aerial Vehicles (MAVs) in order to obtain a good feedback for the attitude controller. The challenges come from the low accuracy and noisy data of the MicroElectroMechanical System (MEMS) technology, which is the basis of modern, miniaturized inertial sensors. In this article, we describe a novel approach to obtain an estimation of the orientation in quaternion form from the observations of gravity and magnetic field. Our approach provides a quaternion estimation as the algebraic solution of a system from inertial/magnetic observations. We separate the problems of finding the …

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Comparative Sorption Of Methylene Blue Onto Hydrophobic Clays, Alvaro D. Sponza, Natalia J. Fernandez, David Yang, Karla A. Ortiz, Abel E. Navarro Aug 2015

Comparative Sorption Of Methylene Blue Onto Hydrophobic Clays, Alvaro D. Sponza, Natalia J. Fernandez, David Yang, Karla A. Ortiz, Abel E. Navarro

Publications and Research

Chemical modifications of clay to remove methylene blue (MB) from aqueous solutions at room temperature were compared. Natural bentonite (NC) was modified by cation exchange with hexadecyltrimethylammonium chloride (HC), bencyltriethylammonium chloride (BC), and tetramethylammonium chloride (TC) to reverse the surface polarity of the hydrophilic bentonite. The adsorption of MB was studied and fitted by the adsorption theories of Langmuir, Freundlich, Dubinin-Radushkevich, and Temkin. Equilibrium parameters were calculated, indicating that chemical modification did not improve the adsorption, due to the electrostatic adsorption mechanism. Specific surface area was determined, reporting the following trend: NC > TC > BC > HC. Isotherms show that TC is …

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Polycations Xxii. Ru(Bpy)2l2 And Ru(Phen)2l2 Systems With Cationic 4,4’-Bipyridine Ligands: Syntheses, Characteristics, And Interactions With Dna, Jasmine Hatcher, Freida Zavurov, Leslie Babukutty, Thomas Strekas, Robert Engel Aug 2015

Polycations Xxii. Ru(Bpy)2l2 And Ru(Phen)2l2 Systems With Cationic 4,4’-Bipyridine Ligands: Syntheses, Characteristics, And Interactions With Dna, Jasmine Hatcher, Freida Zavurov, Leslie Babukutty, Thomas Strekas, Robert Engel

Publications and Research

Earlier efforts have been concerned with the association of Ruthenium octahedral complexes with DNA. Since the positively charged ruthenium species has been found to associate with the electron rich major groove of double-stranded DNA, it was proposed the addition of cationic sites on the ligands attached to ruthenium would facilitate such association. Thus, we have synthesized several series of octahedral ruthenium complexes bearing ligands having within themselves cationic sites. These have been investigated in their interaction with calf thymus DNA using fluorescence titration analysis. The introduction of the cationic ligands has been found to exhibit enhanced association of the ruthenium …

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Respondent-Driven Sampling: Evaluating The Effects Of The Cure Violence Model With Neighborhood Surveys, Kwan Lamar Blount-Hill, Jeffrey A. Butts Aug 2015

Respondent-Driven Sampling: Evaluating The Effects Of The Cure Violence Model With Neighborhood Surveys, Kwan Lamar Blount-Hill, Jeffrey A. Butts

Publications and Research

This report gives insight into how researchers at the John Jay Research and Evaluation Center used Respondent-Driven Sampling (RDS) to measures changes in violence-related attitudes and values of young men (age 18-30) in at-risk neighborhoods and compares areas with and without Cure Violence programs. The RDS method allows researchers to reach difficult-to-recruit populations and helps to increase the credibility of the study.

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Reducing Mass Incarceration: Exploring The Values Of Values, Jeremy Travis Aug 2015

Reducing Mass Incarceration: Exploring The Values Of Values, Jeremy Travis

Publications and Research

No abstract provided.

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